Sash lock



April 13, 1937.

W. C. WITHER LY SASH LOCK Original F'ile'1 July 5l, 1934 Patented Apr. 13, 1937 UNHTED STATES SASH LOCK William Clifford Witherly, Vancouver, British Columbia, Canada Application `luly 31, 1934, Serial No. 737,810. Renewed June 1'7, 1936. In Canada August 5,

2 Claims.

My invention relates to improvements in sash locks, which are particularly adapted for use with sliding sash windows to permit them to be set in any desired position and lock them against opening beyond said position to prevent intrusion by burglars or prowlers. Further objects are to provide such means as can be easily applied to old or new window sashes with such tools as the householder usually possesses, so that the servl ices of skilled artisans are not required to install the locks. A still further object is to provide means which will not only serve to lock the sash in a set position but will serve to prevent the sash from rattling due to wind uctuation and the l like.

The invention consists essentially of 'a housing adapted for insertion into a mortice in the sash, an olset pawl urged into engaging position by spring action and having means for withdrawing the pawl from engagement, as will be more fully described in the following specification and shown in the accompanying drawing, in which:-

Fig. lis a sectional elevation of the sash lock.

Fig. 2 is a sectional View taken on the lin-e 2--2 of Figure l.

Fig. 3 is a sectional elevation of a modification.

Fig. 4 is a sectional elevation of a further modiiication.

Fig. 5 is a sectional view taken on the line 5--5 of Figure 4.

Fig. 6l is an end elevation of the device shown in Figures 4 and 5.

Fig. 7 is a fragmentary View of a window showing the position of the device as applied to the lower sash.

In the drawing like characters oi reference indicate corresponding parts in each figure.

The numeral indicates generally a window of which 2 is a sash stile and 3 is a pulley stile aganst which the sash stile 2 slides.

The numeral l indicates the sash lock, see Figures 1 and 2, which is provided with a casing 5 having side walls 6, an end wall 'I and a flange 8 surrounding its exposed end which forms a stop to prevent the casing from sinking into the mortice made in the sash stile 2. In the end wall l a recess 9 is formed in which a pawl I0 is fulcrumed,

the pawl is fitted at its free end with a Contact button I I which is pivotally connected thereto in any suitable manner. The pawl is urged in a downward direction (when the device is fitted to a lower sash) by a spring l2 serving to thrust the Contact button outwardly from the casing 5 and into contact with the pulley stile 3.,

Rotatably mounted within the casing 5 is a cam I3 which is provided with an internal thread I4 and is slidably engaged by a helix I5 extending from the inner end of a'square pin I6, which latter is slidably mounted in the wall of the casing 5. The pin is fitted at its outer end'with a push button Il between which and the casing 5 a spring I8 is mounted to thrust the pin outwards and rotate the cam out of engagement with the pawl I0.

In the modification shown in Figure 3, the pawl Ill is substantially triangular in form and is adapted to be fulcrumed at two points at the ends of its base as at I9 and 20 respectively, as its button Il is brought into engaging position, the object being to provide for a relatively slow outward thrust of the button when the point I9 is the fulcrum and a relatively rapid thrust when the point 2li is the fulcrum. In this construction a forked lever 2l engages the pawl and has its free end extending through the end wall 'I of the casing Ei and through the sash stile 2 to provide a means operable from the inside of the sash for holding the button 9 out of engagement with the pulley stile 3. v

In the modification shown in Figures 4, 5 and 6 the casing 5 is fitted with a spindle 22 having a crank disc 23 at one end and a turn button 24 at the other, the crank disc is fitted with a crank pin 25 which is adapted to engage the pawl III to swing the button out of engagement vwith the pulley stile 3, and a coil spring 26 is fitted to the spindle and is suitably anchored at its ends torotate said spindle and urge the crank pin away from the pawl that the latter may be free to return to locking position.

In use, when it is desired to open a lower sash the pawl I0 is swung against the thrust of the spring I2 so as to withdraw the button I I towards the casing, thus permitting the sash to be raised freely. When the desired position is attained,

'and the pawl released from manual manipulation,

any upward thrust of the sash will cause the pawl to swing and thrust the button II into forceful Contact with the pulley stile 3, thus preventing v further upward movement of said sash. No manipulation is required of the lock to lower said sash as the button in sliding along thev pulley stile tends to move towards the lock casing 5, so that free movement in this direction is obtained.`

What I claim as my invention is:

1. A sash lock comprising a casing having side walls and a bottom wall, a pawl within the casing adapted to be fulcrumed at two separate points upon the bottom wall, said pawl projecting beyond the casing and being adapted to engage the pulley stile of a Window, spring means for urging the paWl into engaging position, and means operable from without the casing for moving the pawl out of engaging position.

2. A sash lock comprising a casing having side Walls and. a bottom Wall, a substantially triangular pawl floating Within the casing and having its two base points serving as fulcrums for the pawl and being adapted to alternately engage the bottom Wall as the pawl is rocked, the apex of said paWl being adapted to project beyond the casing to engage the pulley stile of a Window, a spring for urging the pawl into engaging position, and means operable from Without the casing for moving the pawl out of engaging position.

WILLIAM CLIFFORD WITHERLY. 

